I think we can safely assume that no tourists ever visited his shop! Not exactly in a prime tourist area. I'm therefore assuming that we're talking about local people here.
Essentially I agree with his actions, although I have issues with the way it was reported (especially by the Daily Heil). He said that if customers made even the slightest effort to use a few English words, he'd go out of his way to help them. Even if this was only 'stamp, please.' But if they made no effort at all, he refused to try to understand them.
I can't say I disagree with this policy (much as I feel that I'd like to). I can think of no reasonable excuse why any immigrant living in the UK wouldn't be able to learn at least two words of English.

